The present invention relates to nil bleach liquid laundry detergent compositions which provide enhanced hydrophilic soil, inter alia, clay, removal benefits. The laundry detergent compositions of the present invention combine zwitterionic polyamines, a polyalkyleneimine dispersant, and a surfactant system which comprises mid-chain branched surfactants inter alia mid-chain branched alkyl sulphates and provides hydrophobic soil removal in the absence of a bleaching system. The present invention further relates to methods for cleaning fabric having heavy clay soil deposits.
Fabric, especially clothing, can become soiled with a variety of foreign substances ranging from hydrophobic stains (grease, oil) to hydrophilic stains (clay). The level of cleaning which is necessary to remove said foreign substances depends to a large degree upon the amount of stain present and the degree to which the foreign substance has contacted the fabric fibers. Grass stains usually involve direct abrasive contact with vegetative matter thereby producing highly penetrating stains. Clay soil stains, although in some instances contacting the fabric fibers with less force, nevertheless provide a different type of soil removal problem due to the high degree of charge associated with the clay itself. This high surface charge density may act to repel some laundry adjunct ingredients, inter alia, clay dispersants, thereby resisting any appreciable removing or carrying away of the clay into the laundry liquor.
A surfactant per se is not all that is necessary to remove unwanted clay soils and stains. In fact, not all surfactants work equally well on all types of stains. In addition to surfactants, polyamine hydrophilic soil dispersants are added to laundry detergent compositions to xe2x80x9ccarry awayxe2x80x9d clay soils from the fabric surface and to reduce or lower the possibility that the clay soil will be re-deposited upon the fabric. However, unless the clay can be initially removed from the fabric fiber, especially in the case of hydrophilic fibers, inter alia, cotton, there will be nothing in solution for the added dispersants to remove. Therefore, there is a long felt need for a detergent system which will ensure that the soils will be removed from fabric so that the surfactants and dispersants can effectively remove the soils and prevent redeposition.
There is a long felt need in the art for liquid laundry detergent compositions which can effectively remove embedded clay and other hydrophilic soils from fabric. The desired laundry detergent compositions will effectively remove the embedded soils and prevent the soils from being re-deposited onto the fabric surface.
The present invention meets the aforementioned needs in that it has been surprisingly discovered that certain zwitterionic polyamines in combination with one or more polyamine dispersants provides enhanced removal of clay and other hydrophilic soils from fabric.
The first aspect of the present invention relates to a liquid laundry detergent composition comprising:
a) from about 0.01%, preferably from about 0.05%, more preferably from 0.1% to about 20%, preferably to about 10%, more preferably to about 3% by weight, of a zwitterionic polymer which comprises a polyamine backbone, said backbone comprising two or more amino units wherein at least one of said amino units is quaternized and wherein at least one amino unit is substituted by one or more moieties capable of having an anionic charge wherein further the number of amino unit substitutions which comprise an anionic moiety is less than or equal to the number of quaternized backbone amino units;
b) from about 0.1%, preferably from about 0.5%, more preferably from about 1% to about 7%, preferably to about 5%, more preferably to about 3% by weight, of a polyamine dispersant;
c) from about 0.01%, preferably from about 0.1% more preferably from about 1% to about 100%, preferably to about 80% by weight, preferably to about 60%, most preferably to about 30% by weight, of a surfactant system comprising one or more surfactants selected from the group consisting of nonionic, anionic, cationic, zwitterionic, ampholytic surfactants, and mixtures thereof; and
d) the balance carriers and adjunct ingredients.
A further aspect of the present invention relates to compositions which comprise:
a) from about 0.01%, preferably from about 0.05%, more preferably from 0.1% to about 20%, preferably to about 10%, more preferably to about 3% by weight, of a zwitterionic polyamine according to the present invention;
b) from about 0.1%, preferably from about 0.5%, more preferably from about 1% to about 7%, preferably to about 5%, more preferably to about 3% by weight, of a polyamine dispersant;
c) from about 0.01%, preferably from about 0.1% more preferably from about 1% to about 100%, preferably to about 80% by weight, preferably to about 60%, most preferably to about 30% by weight, of a surfactant system comprising:
i) from 0.01% by weight, of a mid-chain branched alkyl sulfate surfactant, a mid-chain branched alkyl alkoxy sulfate surfactant, and mixtures thereof;
ii) from 0.01% by weight, of a surfactant selected from the group consisting of anionic, nonionic, and mixtures thereof;
c) from about 0.001% by weight, of a detersive enzyme, said enzyme selected from the group consisting of protease, amylases, lipases, cellulases, peroxidases, hydrolases, cutinases, mannanases, xyloglucanases, and mixtures thereof; and
d) the balance carriers and adjunct ingredients.
The present invention also relates to a method for removing hydrophilic stains from fabric by contacting fabric in need of cleaning with a composition according to the present invention.